In an election between two candidates,one got $55 \%$ of the total valid votes,and $20 \%$ of the total votes were invalid. If the total number of votes was $7500$,what was the number of valid votes that the other candidate received?

Two numbers are respectively $12 \frac{1}{2} \%$ and $25 \%$ more than a third number. The first number is what percentage of the second number?

If the price of a shirt is increased by $25 \%$ and then decreased by $30 \%$,then what will be the net effect?

The population of a city increases at the rate of $5 \%$ per annum. If the present population of the city is $3,70,440$,its population $3$ years ago was:

In an examination,the percentage of students qualified to the number of students appeared from school $A$ is $70 \%$. In school $B$,the number of students appeared is $20 \%$ more than the students appeared from school $A$ and the number of students qualified from school $B$ is $50 \%$ more than the students qualified from school $A$. What is the percentage of students qualified to the number of students appeared from school $B$?

On decreasing the price of a colour $TV$ by $30 \%$,its sale is increased by $20 \%$. The effect on the revenue is: